(a) Technical Field
The present invention relates to a device and method for stacking a fuel cell stack. More particularly, the present invention relates to a device and method for stacking a fuel cell stack, which enables the stacking state of components constituting the fuel cell stack to be accurately stacked using a phosphor.
(b) Background Art
A fuel cell stack is a power generating device that generates electricity via an electrochemical reaction. Recently, fuel cells have been used to provide the main source of power to vehicles as part of the vehicles drive train. A fuel cell stack has a structure in which an anode to which hydrogen is supplied and a cathode to which air is supplied are stacked with a membrane-electrode assembly interposed therebetween. The fuel cell stack refers to a device that generates electrical energy through a chemical reaction of oxygen in the air and the hydrogen supplied from the outside thereof.
A fuel cell stack is often assembled by stacking a few tens to a few hundreds of unit cells. Hereinafter, the configuration of one unit cell will be described with reference to FIG. 3.
First, a membrane-electrode assembly (MBA) is positioned at the innermost side of the unit cell. The MEA includes a polymer electrolyte membrane 10 that enables hydrogen protons to move therethrough, and catalyst layers, i.e., a cathode 12 and an anode 14, respectively coated on both surfaces of the electrolyte membrane 10 so that hydrogen and oxygen can react to each other.
Gas diffusion layers (GDLs) 16 are then stacked on outsides of the MEA, i.e., sides at which the cathode 12 and the anode 14 are positioned, respectively. A separation plate 20 having a flow field formed therein is positioned on an outside surface of the GDL 16 with a gasket 18 interposed therebetween. Here, the flow field is used to supply fuel and to discharge water produced by a reaction therein. An end plate 30 for supporting and fixing the components described above is coupled to the unit cell at the outermost side of the unit cell.
Thus, in the anode 14 of the fuel cell stack, hydrogen protons and electrons are generated through an oxidation reaction of hydrogen. In this case, the generated hydrogen protons and electrons are moved to the cathode 12 through the electrolyte membrane 10 and the separation plate 20, respectively. In the cathode 12 of the fuel cell stack, water is produced through an electrochemical reaction of the hydrogen protons and electrodes are moved from the anode 14 and oxygen in air, and simultaneously, electric energy is generated through the flow of electrons therebetween.
As described above, the fuel cell stack is configured by stacking a few hundred of separation plates, MEAs, etc. If the stacking state of the fuel cell stack is not exactly determined, a leakage of reaction gas and deterioration of cell performance may result.
To solve such problems, a method has conventionally been used in which a separate guide line is applied to a separation plate so that gas and coolant flow fields of an MEA are exactly corresponded to manifolds of the separation plate, respectively, during the stacking of the MEA and the separation plate. However, excessive guide lines may cause crumpling and folding of a thin MEA during the stacking of the MEA.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.